Fluid bearing inertial filter

ABSTRACT

An inertial filter to provide fluid for turbomachine fluid bearings.

United States Patent 1 Schinnerer et al.

FLUID BEARING INERTIAL FILTER Inventors: Roy L. Schinnerer, Long Beach;

Alexander Silver, Tarzana; Leonard T. Sladek; Morris A. Barnett, both ofPalos Verdes Estates,-all of Calif.

Assignee: The Garrett Corporation, Los

Angeles, Calif.

Filed: Feb. 25, 1971 Appl. No.: 118,741

US. Cl. 415/111, 308/DIG. 1, 55/DIG. 14,

Int. Cl. F04d 29/04, F04b 17/00 Field of Search 277/53, 66; 415/111,

' DIG. l4; 308/9, DIG. l

[ 1 June 19, 1973 References Cited UNITED STATES PATENTS 3,038,3186/1962 Hanny 417/407 3,182,897 5/1965 Trumpler 308/9 2,469,846 5/1949Roth et al. 415/112 FOREIGN PATENTS OR APPLICATIONS 358,394 9/1922Germany 55/17 Primary ExaminerI-Ienry F. Raduazo A ttorney- Albert J.Miller and John M. Hazelwood [57] ABSTRACT An inertial filter to providefluid for turbomachine fluid bearings.

10 Claims, 6 Drawing Figures FLUID BEARING INERTIAL FILTER BACKGROUND OFTHE INVENTION For many years, air or gas (fluid) bearings have been anatural candidate for high speed turbomachinery design because of theconvenience and simplicity of utilizing the process fluid, plate airand/or the ambient atmosphere as a bearing fluid or lubricant. While theprocess fluid is most readily available as the lubricant, it is oftentimes impure, typically containing variousquantities of water, dirt,and/or other contaminants. As a result, fluid bearing applications havebeen mainly limited to either closed-cycle systems or. machines wherethe cleanliness of the fluid lubricant could be guaranteed. While fluidbearings have significant advantages, such as design simplicity,relaxation of maintenance and servicing requirements, easing oftemperature limitations, low noise, longer bearing life and in somecases reduced friction, these bearings are particularly sensitive tocontamination in view of the tight clearances and dimensional controlsrequired.

SUMMARY OF THE INVENTION BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 isaschematicside representation of the inertial filter in a turbomachineryscroll.

FIG. 2 is an end view partially in section of the inertial filter in aturbomachinery scroll.

FIG. 3 is a schematic view of the inertial filter in a turbomachineryfluid bearing application.

FIG. 4 is a schematic view of the inertial filter in an alternateturbomachinery fluid bearing application.

FIG. Sis a schematic view of the inertial filter directed towards thenozzle inlet of a round hole nozzle in a turbomachinery nozzle ring.

FIG. 6 is a schematic view of the inertial filter directed towards theinlet of a vaned nozzle.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As illustrated in FIG. 1, theinertial filter generally comprises a probe 10 extending into the mainstream ofa turbomachinery scroll 12. The open end portion 14 of theprobe I is directed downstream such that any flow of air through theopen endl4 of the probe is forced to turn approximately 180 beforeentering the probe. A flow restricting orifice would normally beincluded in the probe 10 to control the fluid flow. FIG. 2 illustratesan end view of the probe 10 within the turbomachinery scroll 12.

The axis of the downstream extending portion 14 of probe 10 is normallyparallel to the stream lines of the main-stream flow in theturbomachinery scroll 12. Thus, any fluid entering the downstream end ofthe tube 14 must essentially reverse direction before entering the probeand any particles in such fluid would not be able to enter the probesince their momentum would carry them with the primary flow past theprobe.

In the fluid bearing application shown in FIG. 3, the inertial filter l0taps air from the turbine scroll '20. This air is supplied through afluid supply line 22 to thrust bearings 24 and journal bearings 26 and28 which support the rotating assembly 29. Orifice 30 in fluid supplyline 22 controls the fluid pressure to the bearings 24, 26, and 28. Thefluid proceeds first to the thrust bearings OD, passes through thethrust bearings from OD to ID and then proceeds axially outward throughthe journal bearings 26 and 28. It is then discharged into the inlet 32of compressor 36 through discharge line 34. The bearing ambient pressureis thus maintained at compressor inlet pressure.

In the modified fluid bearing application shown in FIG. 4, the coolingor pressurizing fluid is drawn by the inertial filter 10 from theturbine casing or scroll 40 to two bearing cavities. Line 42 suppliesfluid to thrust bearings 44 and journal bearing 46 between the turbineand compressor such that the flow is from the thrust bearing OD past thejournal bearing and then discharged at the turbine wheel OD. Line 48supplies fluid to journal bearing 50 between the compressor and the fan.The lower pressure around the bearings causes the flow of air from thehigher pressure turbine scroll.

In order to enhance the performance of the inertial filter, the openprobe end 14 may be oriented towards the nozzle inlets 60 of nozzle ring62 as shown in FIG. 5. The probe may extend substantially up to orslightly into the nozzle inlet and have a cambered end generallytangential to the nozzle ring. This provides the greatest fluid velocitypast the probe and enhances the filtering of dirt from the air enteringthe probe. FIG. 6 illustrates the probe end 14 directed towards a vanednozzle 70.

As shown in FIGS. 5 and 6 the probe end 14 would normally be positionedwith respect to the nozzle ring so as to be directed at least slightlydownward to take advantage of the effect of gravity and thus furtherenhance the inertial filtering.

If more fluid is required than can be conveniently provided by a singleprobe, a plurality of probes can be utilized, each probe extendingtowards a separate nozzle inlet. The fluid from the individual probesmay be combined together into a single line or an individual probe maysupply fluid to an individual fluid bearing. Likewise, where more than asingle row of inlet nozzles are utilized in a nozzle ring, the probe maybe centrally positioned between nozzle rows even if the inlet nozzlesare staggered around the nozzle ring.

While specific embodiments of the invention have been illustrated anddescribed, it is to be understood that these embodiments are provided byway of example only and that the invention is not to be construed asbeing limited thereto but only by the proper scope of the followingclaims.

What we claim is:

1. A turbomachine comprising:

a rotating assembly;

a casing positioned around said rotating assembly to direct the flow ofa process fluid through said rotating assembly;

at least one fluid bearing rotatably supporting said rotating assemblywithin said casing; and

means to supply process fluid from said casing to said fluid bearing,said process fluid supply means including an inertial filter comprisinga tubular member extending into said casing and having an open endfacing away from the direction of process fluid flow in said casing.

2. A turbomachine comprising:

a rotating assembly;

a casing positioned around said rotating assembly to direct the flow ofa process fluid through said rotating assembly;

at least one fluid bearing rotatably supporting said rotating assemblywithin said casing; and

means to supply process fluid from said casing to said fluid bearing,said process fluid supply means including an inertial filter comprisinga tubular member extending into said casing and having an open endportion extending into said downstream in the direction of process fluidflow in said casing.

3. A turbomachine comprising:

a rotating assembly at least including a turbine rotor:

a casing positioned around said rotating assembly and at least includinga turbine scroll having a nozzle to direct the flow of a process fluidthrough said turbine rotor;

at least one fluid bearing rotatably supporting said rotatingassemblywithin said casing; and

means to supply process fluid from said turbine scroll to said fluidbearing, said process fluid supply means including an inertial filterextending into said turbine scroll.

4. A turbomachine comprising:

a rotating assembly at least including a turbine rotor;

a casing positioned around said rotating assembly and at least includinga turbine scroll having a nozzle to direct the flow of a process fluidthrough said turbine rotor;

at least one fluid bearing rotatably supporting said rotating assemblywithin said casing; and

means to supply process fluid from said turbine scroll to said fluidbearing, said process fluid supply means including an inertial filterextending into said turbine scroll, said inertial filter comprising atubular member having an open end portion extending downstream in thedirection of process fluid flow in said turbine scroll.

5. The turbomachine of claim 4 wherein said downstream extending portionof said tubular member is substantially parallel to the flow of processfluid in said turbine scroll.

6. The turbomachine of claim 4 wherein said downstream extending portionof said tubular member extends to the vicinity of the inlet of theturbine nozzle.

7. The turbomachine of claim 4 wherein said downstream extending portionof said tubular member extends substantially to the of the turbinenozzle in the direction of process fluid flow into the turbine nozzle.

8. The turbomachine of claim 6 wherein said turbine nozzle is asubstantially round hole nozzle ring.

9. The turbomachine of claim 6 wherein said turbine nozzle is vaned.

10. The turbomachine of claim 4 wherein the downstream extending openend portion of said tubular member opens in a downward direction.

1. A turbomachine comprising: a rotating assembly; a casing positionedaround said rotating assembly to direct the flow of a process fluidthrough said rotating assembly; at least one fluid bearing rotatablysupporting said rotating assembly within said casing; and means tosupply process fluid from said casing to said fluid bearing, saidprocess fluid supply means including an inertial filter comprising atubular member extending into said casing and having an open end facingaway from the direction of process fluid flow in said casing.
 2. Aturbomachine comprising: a rotating assembly; a casing positioned aroundsaid rotating assembly to direct the flow of a process fluid throughsaid rotating assembly; at least one fluid bearing rotatably supportingsaid rotating assembly within said casing; and means to suPply processfluid from said casing to said fluid bearing, said process fluid supplymeans including an inertial filter comprising a tubular member extendinginto said casing and having an open end portion extending into saiddownstream in the direction of process fluid flow in said casing.
 3. Aturbomachine comprising: a rotating assembly at least including aturbine rotor: a casing positioned around said rotating assembly and atleast including a turbine scroll having a nozzle to direct the flow of aprocess fluid through said turbine rotor; at least one fluid bearingrotatably supporting said rotating assembly within said casing; andmeans to supply process fluid from said turbine scroll to said fluidbearing, said process fluid supply means including an inertial filterextending into said turbine scroll.
 4. A turbomachine comprising: arotating assembly at least including a turbine rotor; a casingpositioned around said rotating assembly and at least including aturbine scroll having a nozzle to direct the flow of a process fluidthrough said turbine rotor; at least one fluid bearing rotatablysupporting said rotating assembly within said casing; and means tosupply process fluid from said turbine scroll to said fluid bearing,said process fluid supply means including an inertial filter extendinginto said turbine scroll, said inertial filter comprising a tubularmember having an open end portion extending downstream in the directionof process fluid flow in said turbine scroll.
 5. The turbomachine ofclaim 4 wherein said downstream extending portion of said tubular memberis substantially parallel to the flow of process fluid in said turbinescroll.
 6. The turbomachine of claim 4 wherein said downstream extendingportion of said tubular member extends to the vicinity of the inlet ofthe turbine nozzle.
 7. The turbomachine of claim 4 wherein saiddownstream extending portion of said tubular member extendssubstantially to the of the turbine nozzle in the direction of processfluid flow into the turbine nozzle.
 8. The turbomachine of claim 6wherein said turbine nozzle is a substantially round hole nozzle ring.9. The turbomachine of claim 6 wherein said turbine nozzle is vaned. 10.The turbomachine of claim 4 wherein the downstream extending open endportion of said tubular member opens in a downward direction.